Volumetric feeder



Nov. 25, 1952 p c ETAL 2,619,261

VOLUMETRIC FEEDER Filed July 21, 1947 3 Sheets-Sheet 1 ERIC PICK GUSTAV R. CARLSSON mmvms Nov. 25, 1952 E. PICK ETAL 2,619,261

VOLUMETRIC FEEDER Filed July 21, 1947 5 Sheets-Sheet 2 d 3/ 32 42 IIIIIIIIIlllllllllllllllll l Fi 2 ERIC PICK,

3 5 GUSTAV R. CARLSSON INVENTORS NOV. 25, 1952 E, cK tr 2,619,261

VOLUMETRIC FEEDER Filed July 21, 1947 s Sheets-Sheet s ERIC PICK m9 GUSTAV R. CARLSSON IN V EN T 0R5 Fig.5 BY

Patented Nov. 25, 1952 VOLUMETRIC FEEDER Eric Pick, East Rockaway, N. Y., and Gustav It. Carlsson, Cliffside Park, N. J assignors to The Permutit Company, New York, N. Y., a corporation of Delaware Application July 21, 1947, Serial No. 762,396

4 Claims.

This invention relates to volumetric feeders; and it comprises apparatus for measuring and dispensing fluent materials volumetrically, comprising a hopper having a vertical axis and adapted to contain a quantity of such materials, a drive pulley and an idler pulley rotatably mounted in a horizontal plane below said hopper and on opposite sides of said axis, power means for rotating said drive pulley, an endless belt passing over said pulleys and having its upper branch facing said hopper, a plurality of transverse partitions on the outward side of said belt, top and side guides for said partitions forming a passageway extending along said upper branch, and an aperture in said passageway in communication with said hopper; all as more fully hereinafter set forth and as claimed.

In many chemical operations it is necessary to feed solid materials in the form of powder or small granules at some definite rate or in some definite proportion to a flow of fluid. For example, in water treatment it is necessary to feed softening agents, coagulating agents or other materials to a flow of water in predetermined proportions. Many types of apparatus have been devised for this purpose. Feeding powdered or granular solids volumetrically and accurately presents difiiculties. Solids will flow somewhat like liquids if they are in the form of small particles, especially if they are agitated or vibrated. a.

On the other hand, there is also a tendency for such materials to arch or cling in the feed hopper. The objects of this invention are to provide apparatus for accurately displacing materials volumetrically, and to provide such apparatus which is efficient in performance, reliable in op er-ation, and relatively simple in construction.

The manner in which these objects are achieved is shown in the appended drawings in which:

Fig. 1 is an elevation of an apparatus in accordance with our invention;

Fig. 2 is an elevation on a larger scale of the feeding mechanism of the apparatus of Fig. 1, with the cover partly cut away;

Fig. 3 is a view, partly in section along lines 3-3 of Fig.2;

Fig. 4 is a view, partly in section along lines 4-4 of Fig. 3;

Fig. 5 is a View, partly in section along lines 5--5 of Fig. 2;

Figs. 6 and 7 are a plan View and an elevation, respectively, of a portion of a modified belt suitable for use in our apparatus; and

Fig. 8 is a view, in section, of the side guide 86 of Fig. 5.

Like numerals refer to like parts throughout the several views.

In the drawings, Fig. 1 shows the complete apparatus. A feed hopper If! is supported from a flange H. While the details of such support are not shown, it is advantageous to mount the hopper on rubber shock absorbers so as to prevent vibration of the hopper from becoming transmitted to the remainder of the apparatus. The top of the hopper Ill is closed by a cover I 2, advantageously provided with a rubber channel I 3 resting on the flange ll. Four pipe supports I4 are welded to the flange H and carry at their lower ends flanges l5, which by means of screws 16, are fastened to the top I! of a mixing tank I8. The mixing tank 18 is provided with a water inlet [9 and with an outlet 20 through which the material being fed is conducted to a point of use in the form of a solution or slurry, as the case may be. To the side of the hopper ID a bracket 22 is fastened by means cf screws 23, and on the bracket 22 is mounted a motor 24 driving an eccentric 25.

A rubber sleeve 21 is fastened by means of a screw clamp 28 to the lower end of the hopper l0 and by means of a screw clamp 29 (Fig. 2) to the top plate 30 of the feeding mechanism. A bracket 3! supporting the feeding mechanism is attached to the top I! of the mixing tank l8 by means of screws 32. To drive the feeding mechanism a variable speed reducer 33 is provided of the type shown and described in Jones Patent 2,405,957, dated August 20, 1946, which is driven by a motor 34 and the output speed of which may be adjusted by turning a crank 35 which varies the speed of a chain 35 driving a sprocket 31.

Referring now to Figs. 2-8, the mechanism has a support plate secured to the bracket 3| by means of screws 4| and dowel pins 42. An opposed plate 43 is secured to the support plate 40 in spaced relationship by means of screws 44 and dowel pins 45. A drive shaft 46 carrying the sprocket 3'! has mounted thereon a drive pulley 41. The drive shaft 46 runs in ball bearings 48 and 49 provided with integral felt seals and mounted in the support plate 49 and the opposed plate 43, respectively, the entry of dust into the ball bearings from the outside being prevented by a felt seal on the side facing the sprocket 31 and by a cover plate 5| on the other side.

An idler pulley 53 is rotatably mounted on a shaft 54 by means of ball bearings 55 and 56 provided with integral felt seals. The shaft 54 is secured by means of screws 5'! to an idler bracket 58 which is slideably mounted in a slot 59 in the support plate 40 and a slot 60 in the opposed plate 43. An idler spring 6|, centered on a stud B2 pressed into. the idler bracket 58 and on a stud 63 screwed into the support plate 40, urges the idler bracket 58 away from the drive pulley 41.

To release the spring tenson, if desired, there are provided two hubs 54 with fingers 65 adapted to engage projections 66 on the idler bracket 58 on rotation of shaft 61 by means of the lever 68. The lever 68 is normally secured in the position shown in Fig. 2 by means of a screw 69, another location for such screw being provided at 10. The idler bracket 58 is prevented from sidewise shifting by a plate 1 I.

A belt 12 is mounted on the drive pulley 41 and the idler pulley 53. This belt carries thereon partitions 13 equally spaced from each other and of lesser width than the belt so as to provide on either side of the partitions strips 18 of belt free of partitions. The partitions 13 advantageously take the form shown in Figs. 6 and 7, the tops 14 of the partitions sloping away from the leading top edges 15 and the sides 16 of the partitions 13 being so made as to result in a decrease in the width of the partition 13, away from the leading side edges 11.

In the top plate which is mounted on the support plate there is provided an opening surrounded by a lip 8I to which the rubber sleeve 21 is fastened by means of the screw clamp 29. Attached to the top plate 30 is a rear top guide 82 and a front top guide 83, the latter being relieved at 84 over the major portion of its length beginning at the end nearest to the drive pulley 41. On the support plate 40 is mounted a supporting shoe 85 to support the upper branch of the belt 12 directly below the opening 80 and thus carry the weight of material in the hopper. On either side of the partitions 13 are mounted side guides 86 and 81, each of which, as shown in Fig. 8, has a guide surface 88 for the sides 16 of the partitions,

a narrow guide surface 89 for the strips 18 of the belt 12 next to the partitions, and a guide surface 90 for the edge 19 of the belt, there being a relieved portion 9|. There are also provided segmental side guides 92 next to the partitions 13 passing over the drive pulley 41.

Angularly disposed scrapers 93, 94 and 95 are forced by the respective springs 96, 91 and 98 against the drive pulley 41, the inside of the lower branch of the belt 12 and the idler pulley 53, respectively.

A framework I00 is secured to the top I 1 of the mixing tank I8 and to the feeding mechanism. This framework I00 supports a side cover H, a rear cover I02 and a front cover I03 which form an enclosure for the feeding mechanism open at the bottom into the top I1 of the mixing tank I8 through an opening I09. The covers, especially the side cover I01, are advantageously secured in place by conventional spring fasteners I04 which permit quick and easy removal for inspection or servicing. On the front cover I03 is an inspection door I05 provided with a knob I06 and slideable in tracks I01. This inspection door is advantageously made of transparent material, such as a transparent plastic, to permit observation of the feeding mechanism during operation.

In operation of our apparatus the hopper I0 is filled with powdered or granular material IIO which is to be fed. The motor 24 is placed in operation thus rotating the eccentric 25 and imparting vibration to the hopper I0 which keeps the material IIO moving. The motor 34 is likewise placed in operation and the crank 35 is turned to a position corresponding to the desired rate of rotation of sprocket 31 and drive pulley 41. As the belt 12 moves, its upper branch sliding over the supporting shoe 85 passes under the opening 80 so that the material I I0 falls through the opening 80 into and fills the spaces between the partitions 13 and the side guides 86 and 81. As the partitions 13 move through the passageway formed by the side guides 09 and 81 and the top guides 82 and 83 they carry the material I I0 towards the drive pulley 41. When the belt passes over the drive pulley 41 the material IIO drops out, as shown in Fig. 4, and falls through the opening I 09 into the mixing tank I8. Because of the bending and resulting distortion of the belt 12 around the drive pulley 41 any clinging of material to the belt is prevented, resulting in an accurate volumetric discharge of the material I I0 into the mixing tank I8.

As the pulleys 41 and 53 rotate and as the belt moves, the angularly disposed scrapers 93, 94 and 95 remove any material which may have reached the surfaces upon which the scrapers rest and these surfaces are thus effectively kept clear of the material being fed. Any material removed by the scrapers drops through the opening I09 into the mixing tank I 8.

A continuous stream of water admitted into the mixing tank through the inlet I9 enters in the form of a jet and thus keeps the contents of tank I0 agitated. When soluble materials are being fed they dissolve; when insoluble materials are being fed a suspension or slurry is being formed. The solution or slurry, as the case may be, is discharged through the outlet 20 whence it flows by gravity or by pumping to the point of application.

When feeding of materials at a constant rate is desired the apparatus is allowed to operate in this manner, the desired rate of feed being adjusted by turning the crank 35. When, however, Water is being treated at a varying rate of flow the feed of material can be proportioned to such varying rate of flow. This may, for instance, be done by operating the feeding mechanism for a predetermined period of time whenever a given volume of water undergoing treatment has passed through a water meter. A control device suitable for such arrangement is disclosed in U. S. Patent 2,204,097 of J. M. Montgomery, dated June 11, 1940.

An important feature of our invention is the arrangement of the top guides 82 and 83 which are equal in length to the spacing of any two adjacent partitions 13. In this manner, at least one of the partitions 13 always has its top 14 beneath each of the top guides, thus forming a lock which prevents the free flow of material from the hopper. On the other hand, it is undesirable to make the top guides appreciably longer than the specing of the partitions because then they introduce additional friction.

When granular materials are being fed it is important to avoid parallel surfaces, one of which moves past the other, as this would allow grains to enter between such surfaces where they would cause an added load on the drive mechanism and greater wear. For this reason the relief 8 3 is provided in the frontal top guide 83, a similar relief is provided at 9| in the side guides 88 and 81 (see Fig. 8), and the partitions 13 decrease in height from their leading top edges and in width from their leading side edges (see Figs. 6 and 7). With this arrangement any material lodged between the sides of the partitions 13 and the side guides 86 and 81, or between the tops of the partitions 13 and the top guide 83 becomes looser as the belt moves and is relatively free, instead of being wedged and squeezed in these narrow spaces when the sides and tops of partitions 13 are parallel to the side guides 86 and {E1 and the top guide 83, respectively. This is particularly important when the material is of granular or crystalline nature.

The parts of the feeding mechanism must, of course, be made of materials of construction suitable to Withstand the chemical action of the materials being fed. The belt 73 is advantageously molded of soft rubber with the partitions l3 integral therewith. It is advantageous to mold strips of cloth into the belt 13 so as to prevent excessive stretching, any minor stretch of the belt being automatically taken up by the spring 6| pushing the idler pulley 53 away from the drive pulley 41 and thus maintaining the belt under tension.

If replacement of the belt 72 is required, the side plate 10! is taken oif, the screw 69 is then removed and the lever 68 lifted until the screw 69 may be screwed through the lever into the tapped hole 70. In this position the fingers 65 push against the surfaces 66, thereby retracting the idler pulley 53 and releasing tension from the belt 72. The screws (not shown) which hold the side guide 81 to the top plate 30 may then be removed whereupon side guide 81 is taken off. This permits removal of the belt and insertion of a new one.

While we have shown and described what we consider the preferred form of our invention, modifications may be made Without departing from the spirit of our invention and reference is therefore made to the following claims for a definition of the scope of our invention.

What we claim is:

1. Apparatus for measuring and dispensing fluent materials volumetrically, hopper having a vertical axis and adapted to contain a quantity of such materials, a drive pulley and an idler pulley rotatably mounted in a horizontal plane below said hopper and on opposite sides of said axis, power means for rotating said drive pulley, an endless solid belt passing over said pulleys and having an upper branch facing said hopper, a stationary support for said upper branch, a plurality of transverse partitions on the outward side of said belt, said partitions comprising a i being of lesser width than said belt so as to provide on either side of said partitions strips of belt free of partitions, top guides for said partitions, side guides for said partitions adjacent to said strips, said top and side guides forming a passageway conforming to the shape of said partitions and extending along said upper branch, said passageway having an aperture in communication with said hopper, and an additional narrow guide surface adjacent to the lower edge of each of said side guides, each of said additional guide surfaces facing one of said strips and having a width equal to a fraction of the width of said strips.

2. The apparatus of claim 1, the one of said top guides toward which said upper branch of said belt is moving in a direction from said aperture providing a clearance to the tops of said partitions which increases in a direction away from said aperture.

3. The apparatus of claim 1, said partitions having leading top edges and decreasing in height in a direction away from said leading top edges.

4. The apparatus of claim 1, said partitions having leading side edges and decreasing in width in a direction away from said leading side edges.

ERIC PICK. GUSTAV R. CARLSSON.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 1,422,002 Shaw July 4, 1922 1,547,276 Wentz July 28, 1925 1,674,634 Brueggemann June 26, 1928 1,906,664 Thorne May 2, 1933 2,020,435 Schaub et al. Nov. 12, 1935 2,034,876 Morgan Mar. 24, 1936 2,141,044 Rassmann Dec. 20, 1938 2,204,097 1 Montgomery June 11, 1940 2,286,143 Lee June 9, 1942 2,307,008 Bostick June 5, 1943 2,400,667 Toews May 21, 1946 

